


one-shots (NSFW warning)

by CharaKohai



Category: Undertale
Genre: Multi
Language: English
Status: In-Progress
Published: 2021-02-14
Updated: 2021-02-14
Packaged: 2021-03-16 03:47:35
Rating: Explicit
Warnings: Rape/Non-Con
Chapters: 1
Words: 2,681
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29447271
Author URL: https://archiveofourown.org/users/CharaKohai/pseuds/CharaKohai
Kudos: 5





	one-shots (NSFW warning)

Warnings: rape; drugs; sperm-milking-machine

Error woke up with a strange sensation within his lower area. He could hear strange noises of both vocal and mechanical variety. His mind wanted to move to see what was happening but something was keeping him pinned in place. Feeling a strange liquid enter his soul, Error shot his eye sockets wide open.

In disbelief, he saw Nightmare holding a now empty syringe and a wide smile paster across his face. Error wanted to ask him what is going on but a loud mew was all that came out. Nightmare looked pleased with himself as he caressed Error's cheekbone.

"Good evening Error" Nightmare spoke softly, "I trust you are feeling really good right now."

"What's going on?" Error stuttered as he finally got words out. 

Nightmare's expression didn't change, "Oh don't worry about that. Just focus on relaxing." 

One of Nightmare's tentacles rubbed Error's inner leg. This was when Error notice that he lacked all forms of clothing. Error face went flushed as he struggled in his restraints but they wore tightly fixed into place. 

Nightmare made a small tsk sound, "Didn't I say that you should relax? It seems like you need a bit more... help than the others." 

"Help? Others?" Error squeaked out.

Nightmare's hand trailed along Error's pelvis and up to his spine. Error took a shaky breath as he tried not to crash from the sensation. Turning his head away, Error tried to say that he didn't like this but words wore failing him at that moment. Instead of the usual painful experience that came with the touch, it felt... good... strangely good.

"Don't worry, I'll make sure the first round goes pleasant for you" Nightmare cooed, "You should be right at home after that." 

Before Error could attempt a reply, a tentacle rubbed Error's pelvis. He tried to hold back a moan as the slick appendage molded itself to touch every part of his pelvis and tailbone. It was almost like somebody plop an actual blob of slime onto him as it seeped into all the little nooks and crannies. 

"N-no" Error breathed out finally.

Nightmare bent down and kissed Error's cheek, "So, you want it rough? I can tell that you're a bit of a masochist based on how much you enjoy your playtime with Ink."

The tentacle was suddenly pulled away like ripping off a band-aid. Error gasp in pain but let out a small moan of pleasure. He didn't understand why it felt so good at that moment. Maybe that strange liquid that was now pumping in Error's soul was messing with his senses. 

Nightmare bent down and bit Error's top rib close to his neck bone. The sharp pain mixed with bliss filled his mind as Nightmare's teeth sunk to his marrow. The bliss seemed to threaten to send Error into a wave of losing self-control as tentacles sharpen themselves to scrap the scared over bones. A slow painful yet blissful sensation of being in the heat of battle that fascinated Error over the eons of battle thought grew with each passing breath.

Unable to hold back the wave of magic now coursing through his bones, Error's magic summons a new ligament. A tentacle was poking the tip of Error's dick as Nightmare was sensing the organ blindly. Nightmare now pulled his teeth away as a cyan tongue licked the oozing marrow. 

The tentacle slowly pokes into the tiny hole at the tip as Nightmare got a feel for ectoplasm. Error couldn't tell if it was painful or pleasurable as it wiggles around inside the tight-fitting space. Nightmare notices a small about of drool that started to seep out of the tightly clutched yellow teeth as he wipes it away.

"See doesn't that feel good?" Nightmare cooed, "Doesn't make you want to melt away?"

The main processor of higher levels of thinking slowly grided to a halt as Error was starting to have trouble focusing on the current predicament he was in. The radiation of bliss was infecting his whole mind as it grew more contagious to his sense of self. The only thing that could pass through his clouded mind was the current experience his body was being brought through. 

"Let's take this further" Nightmare sounded amused with Error's face.

A tentacle wrapped around the penis completely sealing the hot ectoplasm into its cool gelatin form. A wave of pressure started at the tip and made its way down. Error couldn't help but moan as these waves grew in rate and pressure. Almost as if it was mimicking the act of thrusting into a tight hole. A few times, Error could have sworn that three of these waves wore active at once adding more to the pleasureful sensation.

"That's a lovely tune" Nightmare spoke as if he was thought Error's moans were cute, "How about we make you sing so much louder?"

Error's mind couldn't process the intense rate that Nightmare tentacles started to pulse at. He didn't know how long he could last as he gasps and moaned. It wasn't long before a pressure build-up inside of Error begging to be released into the open world. Nightmare notices this as he brought out a strange tubular device that was hooked up to a larger machine.

"Let's see if we can't time the transfer perfectly" Nightmare hummed. 

Right when Error thought he would explode from the pressure inside, the tentacles pulled away allowing a safe squirt of release. But instead of ending up in the free air, it was sucked into the tubular device as it was secured in place of the tentacle. Error felt his seed both ejaculating normally and being sucked out by the device as he moaned out loudly. 

The device collected every last precious drop like it was gold into a nearby jar. An ectoplasm seed of blue gel slushed around as Nightmare grin grew. As if Error wasn't supposed to be done yet, the device was applying a similar method of pleasure that Nightmare was just doing. 

"There we go" Nightmare looked at the jar in amusement, "Let me know if you're running dry so I can give you a boost." 

Error could only make lewd sounds as his night of pleasure was just getting started. With that Nightmare walked away to another unit of the same nature. He first studies the jar before gazing over his victim.

"Cross, you've been a very good boy tonight" Nightmare cooed as he prepared a shot, "But we need just a bit more before you can rest tonight." 

"N-Nightmare a-ah" Cross moaned out, "W-why?"

Nightmare motions wore smoothed as approached Cross, "Why? Because your sperm is so precious and we need it to fertilize the babies." 

The injection was quick as Cross shiver at the sensation. Cross admitted that he found Nightmare attractive but it felt like Nightmare was taking his affection too far. There was a limit to how much Cross could love somebody.

"You're sperm will help create so many children" Nightmare chuckled, "Isn't that what you wanted? Always calling me senpai all the time."

Cross panted as he tried to speak, "B-but not like this." 

Nightmare's grin falters as he wanted to lash out. His tentacles whip the air making small cracking sounds. Not pretending to be gentle, Nightmare shoved one of his tentacles into Cross's mouth.

"Ah, ah, ah" Nightmare tried to calmly speak, "That's not the type of sounds we make here, so let me clean that mouth of yours. Maybe that would change your mind." 

The tentacle brushed along Cross's teeth as if it was actually a toothbrush that was also being shoved down the skeleton's throat. Cross whined at the experience but couldn't make any coherent words.

"Now, we only need more dosage and we're all done for the night" Nightmare explained, "Let's see how far I need to go to get some of your high-grade level of sperm." 

Wanting to put up a fight, Cross tried to chomp down onto the tentacle as hard as he could muster. However, the thick stiff yet squashy material of the tentacle was unfazed to the intence attempts of chompings. 

"Cross, why so reluctant? Normally you're so stubborn for my attention" Nightmare sighed, "Now that you have my full attention, you don't want it anymore? Don't be so mean." 

Nightmare reached down to the suction device and slowly ran his fingers along the base of the device touching Cross's ectoplasm ever so lightly. In a sudden wave of anger, Nightmare gripped onto the large nuts and squeezed them. Cross attempted to scream in pain but it didn't make it past the goop that blocks his passageway.

"I wonder if I can simply squeeze the last droplets from your sacks" Nightmare's voice was lace with threatening venom. 

A few moments before Nightmare relaxed his grip. Soon he started to pleasure the once squeezed body part. Cross's demeanor slowly changes as the shot from earlier slowly filled his bones. Slowly his mind shut down as he sensed the bliss of his treatment. Nightmare removed his tentacle now that he could tell that Cross was going to behave now.

"S-senpai, please don't stop" Cross couldn't help but moaned out now that he was fully under the medication and soft bliss. 

"Now that's the Crossy I know" Nightmare cooed and kept pleasuring. 

His once bitten tentacle now slowly stroke the warrior's spine. Cross's natural reaction was to arch his spine to the sudden sensation along his body. Nightmare increased the suction that the device was applying. He needed to make sure the last drops would make it all the way to the bank. 

Cross couldn't help but cum one final time as the pleasure put him over the edge. Exhausted, Cross passed out as soon as he was done. Nightmare slowly turned off the machine so he could remove the device. After removal, Nightmare left Cross there so he could take the jar of fresh cum to where it needs to go.

In a room just to the side, several nests filled with tiny black orbs wore lined along the walls. Each of these orbs was an egg that will one day turn into a small monster child. These children will one day help Nightmare in his quest for taking over the multiverse but as of now, they need a father donor. 

Taking a small syringe and filling it with the cum from the jar. Nightmare worked quickly to fill the eggs with the necessary filiating materials. Nightmare used each tentacle to aid this effort and soon a whole nest was ready for incubating. 

"That's it sweet children" Nightmare cooed, "drink the milk I harvest for you, so you'll be strong monsters when you hatch." 

The orbs shimmer with the magical light as if agreeing to Nightmare's request. Satisfied, Nightmare return to where he kept the gang so he can continue to monitor their progress. There wore so many children that needed to be fertilized and the night was still young. 

Dust and Horror had been dating these past weeks and it really paid off in Nightmare's favor. The two wore both in a natural heat cycle and could stay strong the entire night. The two wore currently busy pleasuring each other since they knew they couldn't fight back against Nightmare. The drug of heat was too strong for them to fight off anyway so helping each other through the story night was all they could do. 

"Half-filled on your third jar already?" Nightmare grins, "At this rate, we'll have ten jars each from both of you when the night ends." 

Their eye lights wore strongly lighted hearts from the heat they wore experience at the moment. Dust and Horror kept each other plenty pleased as they stayed in the 69 positions. Licking and rubbing the other's exposed ectoplasm like this was the last night of their lives. Horror was starting to bite as he felt more hungry from all the energy he's been squirting out. 

"H-horror, t-too much" Dust moaned as he orgasms, "I-I'll keep on- a-ah." 

"Looks like somebody is starting to crave some rocky mountain oysters" Nightmare chuckled as he grabs a meal supplement pill.

Nightmare didn't want Horror to accidentally eat his mate. It'll be quite painful to keep magic exhausted Dust alive if Horror did bite off a chunk of ectoplasm. He needed both of them safe for harvesting for the next month or so anyway. 

Shoving the pill down Horror's throat, the hungry male didn't hesitate to swallow and continue to pleasure Dust. It wasn't long before fresh cum came from Horror now that he was feed. Nightmare would watch the two but he had one more victim to check on. 

"Killer, you seemed a bit dry tonight" Nightmare hummed as he tapped the near-empty jar.

Killer whimpered, "It hurts." 

"It does, we should fix that then" Nightmare went over to Killer's side, "After all, we wouldn't want our prized lamb to be injured." 

Killer felt relieved when his shackles wore released but it didn't last long. Being place on Nightmare's lap, Killer wonder just was going to happen next. A smooth wave of gelatin messaged Killer's bones as if searching for a wound. 

"Can you tell me what hurts?" Nightmare spoke so softly as his tentacles failed to find anything. 

"M-my soul" Killer spoke out dryly. 

Nightmare study Killer's soul as he wonders what the issue could be. It was slowly changing shape back to its normal monster form which was never a good sign. A hand softly touches the soul at first before tightly squeezing it into its more proper form. Killer let out a short gag before gasping for air.

"How's that?" Nightmare asked, "Not too rough?"

Killer panted, "Mnn, N-nightmare." 

"The others are doing fine, so let's have some fun together" Nightmare offered, "Shall we?" 

Killer didn't get a chance to rebuttal as he was lifted and forced down onto the table face first. A hand circles around Killer's rear entrance as if threatening to breach the tight area at any moment. 

However, it was a tentacle that was thrust inside when Killer least expected it. A cold chilling slime pushed its way into Killer's hot ass before quickly pulling out. Killer didn't have time to breathe when the tentacle came back in but much further. This pattern continues as the tentacle made its way into Killer's magically form stomach. This left Killer drooling onto the table from the pleasure. 

"I enjoy that face your making Killer" Nightmare lewdly spoke, "Makes me want to go all the way through." 

Killer couldn't help but cum at the thought of Nightmare's tentacle coming out of his mouth. Nightmare took this as a sign to keep going. The tentacle made its way into Killer throat as Nightmare focus hard on which direction each section of the tentacle needed to go in. Nightmare could easily break the entire network of the track if he wasn't careful enough.

"Killer, you're so tight" Nightmare mewed out as he kept focus. 

As the tentacle peaked out of Killer's mouth, Killer rolled his eyes lights back in the current pleasure of the experience. Sure it lightly burns to have organs that wore never meant to be abused in such a way be filled so wonderfully, but the pleasure of having a whole tentacle inside of his entire body was so much. 

It wasn't long before Killer experiences a huge orgasm that he had trouble recovering from due to his airway being partway blocked. Nightmare was glad that the dry spell didn't last long now that Killer had plenty of help to turn it into a rainy season. 

Killer's downpour was so strong that it didn't take very long to fill the jar up. Nightmare carefully removes his tentacle so Killer could get some proper rest. Now all was left was to take care of the jar and check on the other stragglers again. Nightmare's army was growing quickly and he had all the resources he needed for the final battle right here.


End file.
